In this technical field processes and equipment are already known which enable the fabrication of tire reinforcements to be integrated with the assembly of the tire itself. This means that rather than having recourse to semi-finished products such as reinforcement plies, one or more reinforcements are made in situ, as the tire is being fabricated, and from a cord spool. Among the processes and equipment, the solution described in patent application EP 1 122 057 is well suited to the production of carcass reinforcements on a rigid core whose outer surface corresponds essentially to the shape of the internal cavity of the final tire. The document describes a device in which the cord intended to form a carcass reinforcement is positioned in contiguous arcs on a rigid core by a mechanism having at least two arms arranged in cascade, which undergo a back and forth movement around the core so as to put in place, progressively and in a contiguous manner, an arc each time it moves one way and an arc each time it moves the other way, with pressing elements appropriate for applying the ends of the arcs as they are formed on the rigid core. The core has previously been covered with uncured rubber in accordance with the structure of the tire, which has the advantageous property of allowing the arcs to be stuck on and kept in place sufficiently well at least for the purposes of fabrication.
The laying of the cords on the core is the more exact, the closer the eyelet through which the cord passes approaches the core in the zone corresponding to the bead of the future tire. In certain implementations of this invention it is best to add at least a third arm, to allow a closer approach to the base of the tire bead. The problem that arises is to control the actual movement of this end arm. Various ways of controlling the movement of the end arm are possible, but they are all to some extent complex and they add weight to the mechanism.